76 Z1 No Charge

I have searched the archives and have found plenty of good responses for no charge problems. Most of the posts I read though had the basic "three wire charging system" coming out of the stator. With tests that walk you though it. I have a background in electrical, but with any electrical system it is good to have something to refer to. I have ordered a manual but it is a week out. So if anyone has any pointers it would be very helpful.

The problem: No charge at any RPM. Have 12.6 volts at the battery whether the bike is running or not. After a short time the battery goes dead. I recharged the battery to test the charging system. Never got above 12v. It steadily depletes the battery.



Is this a differently phased regulator? if so does any know the readings you should get from the wires individually? And what readings should we have after the regulator?

Thanks for your time.

Is your bike a 1976 KZ900? Ed

That doesn't sound like the correct stock stator wiring for a US '76 Kz900. Are you in a different country possibly? Otherwise the stator may have been swapped from a different bike?

I can dig up the testing routine for the stator out of my manual, but it's possible it's a regulator issue (although I think they usually allow the voltage to go too high when they fail).

That seem to be a later stator. Someone changed engines. You can make it work. I had a 79 motor in a 77 frame and I made it work. Can't remember how. I rode the bike for three years and never had a problem.

A 76 is a KZ900 not a Z1.

Post a picture of the stator side of engine.

Yellow, Pink, and Blue are the three stator wires. Three phase stator. Externally regulated. You need to test those three wires. You can Ohm them any combo of the three should be .7 ohm, or better you can check ACvoltage from each two of the three. Should be 56 ACV. So then you know if the Stator is good or not.

Yes it is a 76 z1. I am not sure if the kz and the z1 are the one in the same.

Here in "File Base" is a wiring diagram. Here you will see what the wire colors are, why there are 5 wires in the harness. Which ones are Stator and which are the switches.
www.kzrider.com/filebase/doc_download/264-z900a45

This was what I was looking for. I was getting 16.7-20.1 acV. Thanks for everyone who replied. Always been a bike owner but nothing with a following like the Kz riders. Posted a picture of the bike. Hopefully this answers any question whether it is a Z1 or a Kz.

Make sure that the wires themselves, going into the stator coils are not having a bad connection. There will be a splice between the actual stator coil winding wire and the colored wires. You could use the OHM function and do a wiggle test at the wiring.
See if you have the Combo Regulator and Rectifier assy. If still a single rectifier and a separate regulator, you would be wise to upgrade to the new combo unit.
z1enterprises.com is one source of the combo setup, oregonmotorcycleparts.com is another. They would also have a stator.

I did look, and it does have the separate regulator. I will look into getting the combo unit, it seems like the way to go. Thanks.

Quite a few of the guy's have done a new wiring harness and spade type ATO fuses to upgrade the old wiring.
(OMR) Old Man Rock is one. Might have a look at his posts if interested. He has one on the Combo install also.

Could you post a picture of the other side? Nice bike.